Оксид бора

Substance identification

Boron oxide (boric anhydride, boron trioxide) is an inorganic compound of boron and oxygen. CAS number 54566-73-3, EC number 259-231-2. English name Boron oxide.

Substance class

Refers to non-metal oxides, boric anhydride. When interacting with water, it gradually hydrolyzes to form boric acid, so the substance behaves hygroscopically.

Purpose and areas of application

• flux for the decomposition of silicates and the main raw material for the production of elemental boron and various borides
• alloying additive in semiconductor materials, catalyst in organic synthesis, raw material for ceramic enamels
• raw materials for heat-resistant glassware, optical and telescope lenses, medical glass (ampoules), electronic glass and glass-ceramic composites
• additive in high temperature lubricants and solders
• fire-resistant additive in paints and enamels
• raw materials for the production of alloy steel and high-energy fuels in the metallurgical industry
• a layer of molten B2O3 when growing GaAs single crystals using the Czochralski method to protect the melt from decomposition on the surface: in this case, a graphite or pyrolytic crucible made of boron nitride is needed to hold the GaAs melt; a quartz crucible is unsuitable
• raw material for dissolving boron in the process of chemical-thermal treatment (diffusion boridation) in mechanical engineering
• used in nuclear energy and electronics industry, as well as in other sectors of the national economy
• stabilizing raw material and additive in industrial glass production
• component in the production and processing of cable materials
• raw materials for the production of dyes

Mechanism of action as a flux

In glass and ceramic compositions, boron oxide reduces the viscosity of the melt at a given temperature, which improves moldability and increases the resistance of the product to damage. As a flux, it decomposes silicates, converting refractory components into more fusible borosilicate phases, and also serves as the main raw material for the production of elemental boron and borides by reduction.

Attributes according to supplier data

The molecular weight in the source data is indicated as 0 - a technical error in the processing of the formula by the supplier; for the monomeric form of B2O3 the actual value is 69.62. EC number: 259-231-2, supplier CAS number 54566-73-3 (referring to oligomeric/polymeric form of boron oxide).

Storage and transportation

Store in an airtight container in a dry place: boron oxide is hygroscopic and reacts slowly with air moisture, forming boric acid, which reduces its technological properties as a flux and alloying additive. Transport in closed packaging, avoid contact with water and high humidity, as well as dust on the skin and in the respiratory tract during packaging. When working, use gloves, safety glasses and exhaust ventilation. The molecular weight data in the supplier's original source is indicated as 0 - a technical unloading error, not a characteristic of the substance.

Synonyms and names

Boron trioxide, boric anhydride are established synonyms in industry practice for the same compound B2O3, used depending on the context: “boric anhydride” is more often used in glass and ceramic technology, “boron trioxide” - in metallurgy and electronics.